This is a renewal application to support the Medical Scientist Training Program (MSTP) at Washington University in St. Louis. The overarching goal of the MSTP is to provide in-depth pre-doctoral training in clinical medicine and biomedical research for individuals desiring careers as physician-scientists. The applicant pool is strong and in the past funding period, the MSTP made significant strides in recruiting diversity students. Medical training is provided by the School of Medicine and research training is carried out in the interdisciplinary graduate programs of the Division of Biology and Biomedical Sciences, and in the Departments of Biomedical Engineering and Anthropology. Together, these graduate programs encompass nearly all contemporary areas of biomedical research. The basic components of the MSTP are: 1) Two years of the preclinical medical school curriculum; 2) Coursework in a biomedically relevant discipline; 3) Three or more years of original, hypothesis-driven research leading to completion of a doctoral thesis; 4) At least 15 months of clinical training; and 5) A wealth of academic and social programs designed to enhance the program and cohesiveness of the student body. The M.D. and Ph.D. degrees are awarded jointly at the successful completion of both components which typically takes 7-8 years, a period shortened by integrating both curricula. Upon completion of subsequent postgraduate training, MSTP alumni will be prepared to enter the workforce as physician-scientists. Based on the track record of this program, the vast majority will join the faculty of te nation's medical schools while others will contribute to the nation's biomedical research enterprise in government laboratories, biotechnology firms, and the pharmaceutical industry. Regardless of their position, their MSTP training will allow them to bridge the gap between the basic laboratory and the clinic. The success of this program is due to strong institutional support and continued funding of this grant. Thus, this renewal application seeks continued support for 55 students annually for 36 months each with the goal of graduating 20-25 MSTP students each year over the period of this grant.